Heartbeats
by Wordsplat
Summary: When Steve is poisoned, and Tony discovers he has a few things he'd like to say. Oneshot, TonyxSteve


**I. Drop**

* * *

Steve was falling.

Not just tumbling, grappling to grab on to something, no; Steve was falling, knocked unconscious by the same blow that knocked him off the roof of a building and too far for any of the Avengers, even the non-flying ones, to break his fall before he broke his neck.

Tony's mind raced for a solution as he raced across the sky, but he was too far away. Even as he commanded JARVIS throw every last drop of energy into his thrusters, he _knew _he was too far away. The solution hit him, quite literally; he strained to go faster, and bumped roughly into Thor as he soared past the god, who was also flying for the Captain.

"Thor, hit me with lightning," Tony commanded.

"Stark, I do not wish to harm yo-"

"Fucking light me up _now!_" Tony shouted, his voice more than a little strained.

Thor uneasily did so, the smallest of jolts he could muster. Tony's suit took in the extra power and shot forward, and, seeing the effect, Thor understood and directed even more lightning Tony's way. At 600% power Tony managed to snag the Captain from the air at the last second and they both crash landed, Tony taking the majority of the damage as he tried his best to keep Steve from hitting the ground.

"Shit," Tony coughed, rolling his shoulders and trying to get some feeling back in his bones. He carefully laid Steve on the ground, then tossed his helmet aside and laid an ear to Steve's chest.

His heart was beating, and Tony collapsed back with a weary, thankful sigh.

_Shit._

"He's alive," he called to the approaching others.

Natasha said nothing, moving him aside to see for herself. She removed Steve's glove and pressed two fingers to his wrist. Thor had landed next to her and was now busy assisting Clint, who was still up on the nearby rooftop, in trying to keep a perimeter around their fallen teammate. Bruce wasn't visible, but the Hulk's roars could be heard well enough that he wasn't a worry. Natasha was focused intently on Steve, clearly listening for something; she didn't seem to hear it, because she shook her head.

"Something's wrong."

"The good Captain is breathing, is he not?" Thor demanded, pausing to look for the rise and fall of Steve's chest, before returning his attention to the battle at hand.

"He is. But his pulse is…sporadic. I think…" Natasha's eyes flickered, and Tony caught the movement as she glanced to a long scratch on Steve's neck. The others were too far or too distracted to see her brief pause, but Tony saw, and Tony swore. Natasha just shook her head again, "He needs medical attention, now. SHIELD, do you copy?"

"We copy," Agent Sitwell's voice came over the intercom.

"While we're waiting, I'll get a scan of him, see what JARVIS can dig up," Tony stood shakily, retrieving his helmet and putting it back on to activate a scan and running it over Steve's limp body, "JARVIS, compare this to initial scans and the old man's research, find anything at all abnormal in his system and let me know."

"Yes, sir."

"Level with me, Natasha," Tony turned back to her, keeping his voice low, private, "You thinking poison?"

She hesitated briefly, before nodding.

"They made it look like they came just to destroy things, and while that may be true of the grunts, I've found that simple destruction is rarely the motive of those running the operation. They seemed focused on Steve from the start; I think they only went after us as a way of separating the group so they could get Steve alone."

Both Natasha and Tony looked guiltily to the unconscious Captain.

"And I fucking fell for it," Tony was angry, yes, but now it was channeled at himself. How could he have been so stupid?

"We all did. My other concern is, did you see when Steve was hit?"

"No."

He'd only turned in time to see the Captain falling, plummeting from the empty sky, and that alone had given him a heart attack and a half.

"They didn't hit him in any way that would make him unconscious," Natasha seemed to be thinking it through, working it out as she spoke, "Clean slice to the neck with some sort of knife. I didn't see them using any kind of knives before they drew it on Steve."

"You think it was specially designed for him?"

"It's my best guess."

"Scan complete, sir," JARVIS informed him.

"Show me the results," Tony demanded, then sorted through the resulting screen of information.

"And?"

"You're right. It's definitely poison, though JARVIS can't identify the specifics without further information, so it's probably homemade. I couldn't say for sure but…" Tony's eyes darted back and forth, taking in the different numbers and figures, "I'm not sure how, but it seems to be isolating the differential chromosomes and mimicking them using some type of chemical, but now those chromosomes can't recognize their own sequence, so they're working to eliminate the foreign presence-"

"English, Stark."

"The poison 'blinded' the serum to it's own cells, so to speak. So now the serum is going to think it's own cells are foreign germs and work to eliminate the unwanted presence. But really, they're just going to be fighting to eliminate themselves."

"The serum is going self-implode?"

"…not really, but close enough."

"And what does that mean for him?" Natasha gestured to Steve, who still hadn't moved an inch. If anything, he looked stiller, and Tony began to feel an acute pain blossom in his chest.

"Nothing good."

"Stark," Tony's intercom buzzed, "Fly him up, we're ready."

He glanced up to see the faintest flickering above that signaled the SHIELD Helicarrier had arrived. He took Steve into his arms without hesitation or another word to Natasha, and took off.

* * *

**II. Flutter**

* * *

Steve was never in sickbay.

The others actively avoided it, sure. Clint's head would have to be separated from his body to find him there, and Natasha probably not even then. Tony whined so much about it that unless he was actively dying nobody even bothered trying anymore, and Bruce understandably didn't like any sort of confined space and was a doctor of sorts anyway, so they let him slide as well. Thor had a bad experience his first time here, and subsequently threatened sending down lightning on the Helicarrier should they try and subdue him again. For the most part they figured it was fine, since he healed better than mortals on his own anyway, and when he was really in need of healing he went home to Asgard.

Regardless of this, every last one of the other Avengers were thrill-seeking danger maniacs in some way or another, and thus ended up in sickbay plenty often in spite of their excuses.

Not Steve.

Steve didn't seek out danger. He fought to protect the city with his team, but he didn't place himself in unnecessary danger the way the others were prone to. In addition to this, his super soldier healing generally made most injuries he received completely ignorable. So though he got more than his fair share of cuts and and bruises and beatings, he had never received anything serious enough to land him in sickbay before.

Then he was poisoned.

Natasha initial assessment was right; it was for him and him alone. Though Tony and Bruce spent weeks debating all the fancy terms and talked for hours about what exactly the process was doing, the simple answer was that the poison was designed to work the super soldier serum out of Steve's system completely, maybe even kill him in the process.

For nearly two weeks, Steve was in complete agony. His body rebelled against him; he didn't heal like he used to, he could hardly move, and his muscles began to wither away. He was becoming the scrawny weakling he once was, and if the pain wasn't killing him the thought of what was happening to him would.

For two long, agonizing weeks, Tony never left his side.

Not when Steve woke up screaming, visions of Bucky falling from the train racing through his mind on replay. Not when he spasmed for hours on end and had to be restrained, so violently was the poison taking over his system. Not even when he punched Tony in the face for waking him, convinced for a moment that the figure leaning over him was there to push him underwater, hold him there until the ice settled in his veins and froze him to his very core. Tony remained by Steve's side, not even leaving to treat his surely broken nose.

Through everything, Tony stayed. Talking softly and stroking his forehead, murmuring nonsense, anything to make Steve feel better, calmer, safer until the fever breaks. When Steve was demented with fever, Tony was a rock; solid and perpetual, the one thing Steve could grab hold of as the fever threatened to drag him under.

In a rare moment, Steve was lucid and awake while Tony had crashed. His head rested against Steve's chest, his stiff chair as close as it could be to Steve's cot. Steve examined him. His face was haggard, his hair disheveled, and in place of his usual clean, neat suit was jeans and an old shirt. Though he was sleeping at the moment, he still looked so tired. The man seemed completely broken down, as if he had been beaten, dragged to Steve's bedside and left there, slumped over like a rag doll. Steve supposed he looked the same. He rested a hand on Tony's, and the man blinked awake. He looked startled for a moment, clearly having fallen asleep by accident, before he sighed softly, squeezing Steve's hand in return. With tired humor, Steve told Tony he should get some real sleep, the in-a-bed kind. Tony said nothing, but graced him with a tired smile that told Steve very clearly that Tony wasn't going anywhere.

Perhaps under normal circumstances, Steve might have thought more about it. Wondered why the ever-sarcastic, everything's-a-joke Tony Stark was so concerned for his welfare. Though they had become good friends since the New York Thing, Steve would have been (under different circumstances) rather surprised at Tony's unusual…gentleness. As it was, he was just infinitely grateful for the man's support. Without Tony's hand to grab when the poison gripping him a little too tightly…Steve wasn't entirely sure he'd be able to handle it. Not that he was taking it particularly well to begin with, but Tony's constant, steady presence let him know he wasn't alone.

And that was enough.

* * *

**III. Steady**

* * *

Another week passed, and Bruce came up with something vaguely close to an antidote. Though it wasn't a complete cure, it did get rid of the poison and stop the serum from continuing to disintegrate itself. Steve was weak, but his powers remained. Not that anyone could care less about his powers; at this point, it was Steve's life they were concerned for.

After they stopped the poison, Steve began to recover. He was awake a little more often, talked very little, even began eating solid foods. Then, without warning, his heart rate plummeted.

Tony had been at his bedside, talking idly with Steve just to keep him awake and aware of his surroundings, when it happened. Steve suddenly convulsed, blinked widely, and went unconscious again as his monitors went crazy. Tony leapt up, shouting for Bruce, as his own heart beat hard enough to break through his chest, because god, it was like watching Steve fall out of the sky all over again. And he was helpless again, completely helpless, just like when he'd been racing through the sky without enough power to get there, to do anything.

Why was he always so fucking helpless?

He called for Bruce, but Bruce either couldn't hear him or wasn't coming fast enough. He demanded JARVIS find Bruce, call a SHIELD medic even, fucking _someone _that could do _something._

Because Tony couldn't do a damn thing to save Steve.

And it _hurt. _He could read the charts, he could see Steve's heart rate dropping lower and lower, see the man's face becoming even more pale than the sickly, un-Steve-like shade it already was, but for once in his life Tony Stark didn't have a clue what to do about it.

And fuck it all if after this was all over and done with, he wasn't going to go get a damn medical degree.

But for now, there was nothing Tony could do, nothing Tony knew how to do; so he talked. He talked and talked, his voice hoarse and pleading. And though Tony Stark had never been one to beg or pray, he would have been on his knees with his hands clasped for either purpose if it would have gotten Steve to open his eyes again.

"Steve? Steve, listen to me, okay, can you hear me? Just listen to my voice, stay with me, Bruce is coming, Bruce is coming and he's going to know what to do, and he's going to make everything okay, alright? Fuck, he's going to make everything okay, because you can't, you can't do this to me, Steve, you can't, we need you here, _I _need you here, okay? Just hold on, Bruce'll be here soon and he'll fix it, he'll fix everything, you're going to be okay, I promise, I fucking swear on my life, I'll make this okay…"

Tony paused, brushing back the soft blonde hair from Steve's forehead. The soldier's forehead was nearly cold, and Tony bit his lip. It wasn't supposed to happen like this, never like this; Tony was the stupid one, the reckless one, always throwing himself in harm's way. It was always Steve at Tony's bedside, and Tony couldn't help but hate himself for all the times he'd done this to Steve. If Steve had felt anything then that was at all close to what Tony was feeling now, it had been a horrible, selfish thing for him to do.

Tony wasn't one for open emotions. Anger, sure, but much else was usually beyond his reach. He was human, of course, and he felt the full spectrum of them, but he had perfected a rather tight lockdown on open displays of it. He'd learnt that particular party trick from his parents, his childhood, and eventually from his adult life of entertaining the masses with his "genius billionaire playboy philanthropist" act. It wasn't real, of course, but it was a beautifully perfected act.

None of this accounted for the tears streaking down his face as he clutched Steve's unusually, heart-breakingly frail hand.

"Please," Tony murmured, his voice soft, almost unheard over the monitor's crazed beeping, "_Please, _Steve, I need you to wake up. I need you, we all still need you. Captain America, right? Duty calls, Steve, wake up, there's a building on fire, a little kid in the street, there's…there's a broken, crazy idiot hiding in an iron suit who has something to tell you, please, just-"

And then, unbelievably, there was a jump.

It was brief, just a brief flicker of a spike, but Steve's heart rate had gone up for just a moment. Tony stared at the monitor for the briefest of seconds, then instantly started talking even faster.

"You can hear me, oh my fucking god you can hear me, Steve, okay, I'll just keep talking, I'll just talk and talk and talk all fucking day if you want, anything you want, anything at all, Steve, I'd do anything for you, you know that, you have to know that, I…" and then Tony paused, because what had Steve heard that jumped his heart rate? And as crazy as it was, he had an idea. Maybe it would work, maybe it wouldn't, but fuck if he wouldn't try anything under the sun right now, "You want to know what I was going to tell you, don't you? Okay, well, this isn't how it's supposed to go and you're really not supposed to say stuff like this when people are basically unconscious and I should have told you this sooner anyway, I should have said anything at all really, but I've always been a procrastinator, even about things that are so clearly important, and I put telling you how I felt off. I put…I put you off. And I'm so sorry, Steve, you can't even…you can't imagine how sorry I am. I should have told you I loved you when it mattered, but I-"

Another spike from the monitor; not a great sign, but a better one than the plunging heart rate it had been showing a moment ago. Tony took this to heart anyway.

"Because I do, god, I do. I love you, Steve. I know we fight and I know sometimes you want to kill me but I love you anyway, you just light up my whole fucking world, you know that? You're just the personification of everything perfect and wonderful and I'm not doing a great job of describing this right now because holy fuck your heart rate is going up and I think that's good and I just, I need you to wake up, because I love you, and I don't think I can do this without you, you mean…god, you mean the world to me, Steve, I just…"

At that Tony trailed off, unable to find any better words, and instead pressed his lips against Steve's insistently, hoping maybe Steve would be able to just understand him without words cluttering everything up.

The heart monitor went crazy again, but from what Tony could tell it was the good way. Tony broke away from Steve just as the blonde's eyes flashed open, and before either of them could get a word in edgewise, Bruce, Natasha and Clint burst in through the double doors.

"What have you been _doing _in here?" Bruce demanded, grabbing Steve's monitor and examining it as Tony and Steve slowly met each other's eyes, curiosity in Steve's and guilt in Tony's, "JARVIS relayed Steve's heart rates to me, first he's dropping off like he's going to go into a freezer state again, now his heart's pumping like a blushing virgin at prom, what ha-"

It was beyond the wrong place and time. Steve was still in critical, Tony was still emotionally wiped, and Bruce had no idea the implication of what he'd just said. In spite of that, Tony couldn't help but laugh uproariously, just as Steve couldn't help turning fire truck red.

"…I don't even know how to respond to that," Bruce blinked at them, "So I'm going to do what I do best with you idiots and ignore it. Steve, you're going to be okay, but you should try and get some more sleep. Your rates seem to have stabilized themselves for now, but we're not out of the woods yet, you could easily have another panic attack. And Tony, if you're going to laugh at him, I'm sure Natasha would love to escort you out."

Natasha cracked her knuckles, and Tony gulped.

"Tony, when's the last time you ate, anyway?"

"Define eating."

"Coffee doesn't count."

"…I honestly do not recall."

"It has been 27 hours at my count," JARVIS reported, and Tony swore.

"Traitor," he scowled.

"I'll get you both something to eat," Bruce sighed, all too used to this idiocy, "Stay here, and Tony, _don't _rile him up, or I swear I'll let the Other Guy have a go at you."

"Yessir!" Tony mock saluted.

Bruce left, but Natasha and Clint remained. Natasha didn't seem particularly interested, but Clint was looking between Tony and Steve with narrowed eyes. At last, he spoke up.

"No fucking way. You did _not _pull a sleeping beauty on _Captain America!"_

"Pull a what?" Steve blinked.

"Shut up, Legolas," Tony scowled, "It's not like you think-"

"It's exactly like I think! You're stealing Steve! That's not fair, you already have Bruce to be your smarty pants science buddy!"

"You still have Natasha and Coulson!" Tony accused, to which Clint made an exasperated noise.

"Natasha's a _gir-" _Natasha raised a deadly eyebrow, and Clint hastily adjusted himself, "A, uh, woman. And Coulson's _Coulson, _he doesn't count. I need a guy friend too you jerk!"

"We're still friends Clin-" Steve attempted to calm the archer, though he still had no real clue what was happening.

"No, now you're gonna be all 'Tony Tony Tony' all the time and kissing and blech!" Clint declared.

"Clint, you're an idiot," Tony rolled his eyes, "Besides, there's still Thor."

"Thor would run around naked and eat poptarts all day if we let him!" Clint moaned, "Steve, how could you? I'm just as good as him! Okay, so maybe Tony has more money than me, and he'll like, kiss you and stuff, which, okay, I won't do that, but I'm way funnier! And I can shoot people with my eyes closed!"

"I don't even know what's going on anymore," Steve looked bewildered.

"Don't even try and win me back, Steve," Clint huffed, "It's over."

"Clint, we were never-"

"Ignore him," Natasha grabbed Clint by the collar, and dragged him out behind her as they left, "Congratulations, Captain. Stark."

And then there was silence.

"I really don't understand what just happened."

"You mean, Clint? Or…?" _Before?_

"I mean Clint. I understand kissing, thank you, I am _not _a 'blushing virgin at prom'!" Steve declared, though he may or may not have been blushing as he did so. And Tony may or may not have found it adorable.

"Bet I can make you blush though," Tony grinned cheekily, stealing another kiss.

This time, Steve whole-heartedly returned it.


End file.
